BruControl ESP32 Format UniShield
The UniShield simplifies the integration of a BruControl interface as it includes multiple functions in one: microcontroller , screw shield, DC power supply, high-current output drivers, user configuration, and DIN rail mount.
This is a shield for the ESP32 Development Board format interface. It is a stacked design, containing a base board for I/O and a riser board for the interface. The ESP32 Development board (included) plugs on top of the riser board and can easily be replaced. The riser and base boards are connected by ribbon cable for efficient packaging. It contains an on-board 3-amp DC:DC power supply (DDPS) to reduce the need for multiple power supplies in the control panel. The DDPS can be powered with 12 or 24 VDC and its output is adjustable from 3 to 12 VDC. It’s output can be switched to either supply the interface via its 5V pin or supply the interface with 3.3V directly (thereby bypassing the interface’s 5 V regulator), or to supply an on-board terminal, creating a discrete DC:DC converter which can be used for other devices such as flow-meters, RTD-amplifiers, etc.
The base board contains 24 high-current outputs (20 are usable with the ESP32) which are split into two banks, enabling each bank to be powered by different sources (e.g. 5, 12, 24 VDC). The current outputs limits are: 3 amps per output, 6 amps per driver (4 outputs each), 15 amps per bank (2 banks). This will eliminate the need for electro-mechanical relays to switch low-current DC. Therefore, contactors, valves, relays, DC pumps can be powered directly. This should reduce panel space and simplify wiring, reducing panel size and overall cost. PWM functions at up to 1000 Hz, enabling a DC pump without any additional hardware. The output drivers are fault tolerant – for example, will not be damaged by an accidental short-circuit.
Each I/O terminal set includes a high-current driver output and a “direct” pin, allowing for devices to be connected directly to the interface pin. Fly-back diodes are included on driver outputs to damp inductive loads such as solenoids and relays to reduce potential electrical noise. Output drivers are enabled by default, but switches are included for each to disable them.
The UniShield includes on-board pull-up resistors for I2C and 1-wire, so external devices such as 1-wire temperature sensors can be easily wired. It contains screw terminals for each I/O point, and also contains terminals for other wiring functions including power, analog inputs, grounds, etc. The unit is housed in a DIN carrier for simplified and universal mounting.
The UniShield comes assembled and tested with an ESP32 interface and pre-loaded firmware. Versions include internal (on-board) or external antenna. External antenna versions include a panel-mount antenna and connecting cable.
Read the UE-1 Product Note for more details, configuration, and installation. Also, here is a Close Look overview video: